A medical headlamp assembly is a critical part of the surgeon's suite of tools, as it is of great importance that a surgeon can clearly see in the operating theater. The ideal headlamp would be easily portable, light and comfortable to wear for at least four hours. Further, it would have battery power, mounted on the headstrap, sufficient to last four hours from one charge, thereby eliminating the necessity of waist mounted battery pack and cables connecting this pack to the lamp, which are uncomfortable and complicate antiseptic protocol. Further the ideal headlamp assembly would create a bright beam of light that was homogenous and uniform in brightness and color, from edge-to-edge, directly along the surgeon's line of sight, without obscuring his or her line of sight. Also, it would be entirely silent, easily adjustable in position and would not be susceptible to infection by mold or any other sort of organism.
Unfortunately, these criteria are not only difficult to meet, but are also frequently at odds with each other. For example, although it is better to have a bright light, this creates more heat, which must be safely expressed from the lamp. It is helpful in the elimination of heat to make the lamp bigger, but doing so is likely to cause it to obscure the surgeon's line of sight and add unbearable weight. Another option for expressing heat would be to provide a fan, but this creates a sound which may be difficult for the surgeon to tolerate. To permit longer battery life it would be helpful to have higher capacity batteries, but doing so makes the assembly heavier and more difficult for the surgeon to tolerate for a long period of time. The batteries could be placed in a waist pack, but doing so requires an electrical line extending from an aseptic area, about the waist underneath the scrubs (anything under the neck is a “sterile” area), to a non-sterile area, on the surgeon's head. This arrangement complicates aseptic protocol.
There is a currently available headlamp assembly that mounts batteries on the headband and that has batteries that can be swapped out, one at a time, for extended surgical periods. The light produced by this headlamp is on the order of 166 lumens in intensity. For many types of surgery, for example where a deep cavity that has been opened up inside a patient requires illumination, a higher intensity lamp is desirable.